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1.
Numerous studies have addressed sex estimation from the hands and feet with varying results. These studies have utilized multiple measurements to determine sex from the hands and feet, including measures of robusticity (e.g., base width and midshaft diameter). However, robusticity measurements are affected by activity, which can disguise underlying patterns of sexual dimorphism. The purpose of this study is to investigate the utility of length measurements of the hands and feet to estimate sex. The sample consists of white females (n=123) and males (n=136) from the Terry Collection. Discriminant function analysis was used to classify individuals by sex. The left hand outperformed both the right hand and foot producing correct classification rates exceeding 80%. Surprisingly, the phalanges were better sex discriminators than either the metacarpals or metatarsals. This study suggests that length measures are more appropriate than robusticity measures for sex estimation.  相似文献   

2.
The forensics discipline of bloodstain pattern analysis plays an important role in crime scene analysis and reconstruction. One reconstruction question is whether the blood has been spattered via gunshot or blunt impact such as beating or stabbing. This paper proposes an automated framework to classify bloodstain spatter patterns generated under controlled conditions into either gunshot or blunt impact classes. Classification is performed using machine learning. The study is performed with 94 blood spatter patterns which are available as public data sets, designs a set of features with possible relevance to classification, and uses the random forests method to rank the most useful features and perform classification. The study shows that classification accuracy decreases with the increasing distance between the target surface collecting the stains and the blood source. Based on the data set used in this study, the model achieves 99% accuracy in classifying spatter patterns at distances of 30 cm, 93% accuracy at distances of 60 cm, and 86% accuracy at distances of 120 cm. Results with 10 additional backspatter patterns also show that the presence of muzzle gases can reduce classification accuracy.  相似文献   

3.
The 1993 Supreme Court case Daubert v. Merrell-Dow Pharmaceuticals, Inc. underscores the importance of validating forensic science techniques. This research examines the validity of using posterior-anterior radiographs of the hand to make positive identifications of unknown human remains. Furthermore, this study was constructed to satisfy the requirements of Daubert's guidelines of scientific validity by establishing a standard methodology for hand radiograph analysis, testing the technique, and noting rates of error. This validation study required twelve participant examiners from the forensic science community, working independently, to attempt to match 10 simulated postmortem radiographs of skeletonized hands to 40 simulated antemortem radiographs of fleshed cadaver hands. The overall accuracy rate of the twelve examiners was 95%, while their collective sensitivity and specificity were 95% and 92%, respectively. However, the accuracy of each examiner was related to the amount of radiological training and experience of the observer. Six Ph.D. forensic anthropologists and four experienced forensic anthropology graduate students correctly identified all the matches. Participant examiners noted bone morphology, trabecular patterns of the proximal and middle phalanges, and distinctive radiopaque and radiolucent features as the anatomical features that aided the identification process. The hand can be an important skeletal element for radiographic positive identification because it contains 27 individual bones for comparative analysis.  相似文献   

4.
A database for footwear outsole designs has been developed on a PC. The database consists of three files: shoes of suspects, shoeprints from the scene of crime and shoes available from the shops. For REBEZO an algorithm is implemented for the automatic classification of outsole patterns. The algorithm first segments the shoeprofiles in different profiles. The Fourier-features are calculated for those profiles. The best Fourier features are selected and are classified with a neural network. By using this algorithm many different shapes can be recognised. Integrating the results of the invariant moments in the neural network will give better results.  相似文献   

5.
Crime scene footwear classification systems can be utilized to look for possible suspects, to get models and brand names for crime scene impressions and to link crime scenes. In this work a computerised footwear classification system is presented. The classification coding of the system has been designed especially for partial footwear impressions which are the most typical in crime scenes. The system is flexible because it is possible to agree within a crime scene investigation unit the way in which the system is to be applied. If outsole patterns are classified accurately in processing for the database, time will be saved in the search process and vice versa. The accurate classification coding is propounded by the fact that only a few experienced users are needed to perform the classification and data storage and all police officers returning from crime scenes are able to perform searches very easily. The users only have to follow the defined rules for geometric shapes. The crime scene investigation unit of the Turku police tested the system for a period of 1.5 years. The system has proved to be of valuable assistance in investigation when several of the hints lead to early solving of a crime. Practical experiences are described.  相似文献   

6.
Carnivore defecation and regurgitation are taphonomic processes that create discrete concentrations of bone pieces and soft tissue fragments of animals that have been consumed. Experiments in which baboon carcasses were fed to leopards and spotted hyenas demonstrate that primate metapodials and phalanges are well represented as readily identifiable specimens in such scat concentrations. Most often phalanges are recovered from scat as whole, articulated digit units (composed of the proximal through distal phalanges) still covered with ligaments, intact skin and finger/toe nails. Considering the very basic similarities between baboon and human physiques, the potential applications of these findings to human forensic cases are significant. Fingers and toes possess features, including fingerprints and, sometimes, distinctive finger and toe rings, useful in the identification of human bodies.  相似文献   

7.
Abstract:  In the field of forensic footwear examination, it is a widely held belief that patterns of accidental marks found on footwear and footwear impressions possess a high degree of "uniqueness." This belief, however, has not been thoroughly studied in a numerical way using controlled experiments. As a result, this form of valuable physical evidence has been the subject of admissibility challenges. In this study, we apply statistical techniques used in facial pattern recognition, to a minimal set of information gleaned from accidental patterns. That is, in order to maximize the amount of potential similarity between patterns, we only use the coordinate locations of accidental marks (on the top portion of a footwear impression) to characterize the entire pattern. This allows us to numerically gauge how similar two patterns are to one another in a worst-case scenario, i.e., in the absence of a tremendous amount of information normally available to the footwear examiner such as accidental mark size and shape. The patterns were recorded from the top portion of the shoe soles (i.e., not the heel) of five shoe pairs. All shoes were the same make and model and all were worn by the same person for a period of 30 days. We found that in 20–30 dimensional principal component (PC) space (99.5% variance retained), patterns from the same shoe, even at different points in time, tended to cluster closer to each other than patterns from different shoes. Correct shoe identification rates using maximum likelihood linear classification analysis and the hold-one-out procedure ranged from 81% to 100%. Although low in variance, three-dimensional PC plots were made and generally corroborated the findings in the much higher dimensional PC-space. This study is intended to be a starting point for future research to build statistical models on the formation and evolution of accidental patterns.  相似文献   

8.
There has been a large increase in research in the last 10 years or so on the nature, extent, and causes of female delinquency, especially on how patterns differ from those of male delinquency. Few research efforts, however, have systematically examined sex differences in the reliability and construct validity of the most common technique used in causal research-the self—report method. The present study addresses this issue by empirically examining male-female differences in self-report reliabilities and the effect of the prevalence and incidence of delinquent behavior on official contact (i.e., arrest, court referrals). Multiple-group covriance structure models are employed to test hypotheses of measurement and structural invariance. The major conclusion is that while self-report measurement parameters (e.g., reliabilities) may differ, the structural link between the prevalence and incidence of delinquent behavior and official contact is generally invariant with respect to sex.  相似文献   

9.
Distinguishing between accidental and abusive head trauma in children can be difficult, as there is a lack of baseline data for pediatric cranial fracture patterns. A porcine head model has recently been developed and utilized in a series of studies to investigate the effects of impact energy level, surface type, and constraint condition on cranial fracture patterns. In the current study, an automated pattern recognition method, or a fracture printing interface (FPI), was developed to classify cranial fracture patterns that were associated with different impact scenarios documented in previous experiments. The FPI accurately predicted the energy level when the impact surface type was rigid. Additionally, the FPI was exceedingly successful in determining fractures caused by skulls being dropped with a high‐level energy (97% accuracy). The FPI, currently developed on the porcine data, may in the future be transformed to the task of cranial fracture pattern classification for human infant skulls.  相似文献   

10.
Abstract: We illustrate an interdisciplinary approach to identify a victim in a case with complex taphonomic and procedural issues. Burning, fragmentation, species commingling, and examination by multiple experts required anthropological preparation and analysis combined with radiographic adaptations to image and match trabecular patterns in unusually small, burned specimens. A missing person was last seen in the company of a reclusive female on a remote rural property. A warranted search found several burn sites containing human and animal bones. Fragment preparation, analysis, and development of a biological profile by anthropologists enabled examination by the odontologist, molecular biologist, and radiologist, and justified use of antemortem radiographs from one potential victim. Visual and radiological comparison resulted in a positive (later confirmed) identification of the victim by radiological matches of three carpal phalanges. Although some dimensional changes are expected with burning, morphological details were preserved, aided by selection of relatively intact, small bones for comparison.  相似文献   

11.
Drawing on databases going back to the middle of the nineteenth century, this article examines how changes in the opportunity structures in political recruitment have influenced the socio-economic backgrounds and career patterns of British and German MPs. Extending opportunity structures enables legislatures to respond to socio-economic changes in society, but there may be a significant time-lag before they are reflected in the legislature. In spite of significant differences in their political history, there has been a convergence of socio-economic backgrounds and career patterns, driven largely by changes in the opportunity structures, which, particularly in the German case, preceded the full impact of changes in political culture. This convergence does not preclude significant differences, but these are principally the product of particular factors, such as party and electoral systems, and changes do not necessarily occur simultaneously, but the tendency towards similar educational and occupational backgrounds and similar career patterns remains.  相似文献   

12.
Based on the classification of hyoid bone into hyperbola-, parabola-, and horseshoe-shaped types, conditions were stimulated under planar and punctiform ventral force as well as in case of strangulation in photoelastic experiment. The results thus obtained were compared to those from former investigations in the field of bone tissue density. Hence, each hyoid type shows characteristic patterns of lesion of its own. The patterns of fractures and localizations which had been expected theoretically could be verified when compared to lesions that occurred in vital state. Then it turned out that horizontal fractures were typical of lesions of hyperbolic hyoid bones and vertical fractures of the cornu maius typical of lesions of parabolic hyoid bones.  相似文献   

13.
This paper reviews trends in black-white incarcerations in the North and South from 1870 to 1980. Using census data on imprisonments it finds that the degree of disproportionate imprisonment of blacks (relative to their representation in the general population) has been higher in Northern states than in Southern states from the middle of the 19th century through the present, although recently the trends have begun to converge. After reviewing explanations for the higher imprisonment rates of blacks in the North, it reviews black-white patterns of arrests and imprisonments by state for 1960, 1970 and 1980 and finds that the variations in black-white imprisonments are not fully accounted for by arrests. Finally, it comments on appropriate methodologies for examining racial differences in treatment in the criminal justice system.  相似文献   

14.
This paper reports the statistical study of writing habits for Arabic Numerals of 187 subjects in Hong Kong. A classification system of writing habits for Arabic numerals based on assigned codes of characteristic features such as slant, writing direction, relative position of strokes, angularity of turnings, shape of initial and ending strokes, etc. was developed. A set of characteristic codes representing the profile of writing habits pertaining to Arabic numerals was assigned to each writer. Apart from the distribution of characteristic features, statistical analysis of the assigned codes demonstrated homogeneity of individual hand-writing patterns. It has been shown that irrespective of the structural simplicity of Arabic numerals, no two individuals exhibited the same set of characteristic codes. The findings support the hypothesis of individuality in handwriting.  相似文献   

15.
16.
A new method that searches for similar striation patterns using neural networks is described. Neural networks have been developed based on the human brain, which is good at pattern recognition. Therefore, neural networks would be expected to be effective in identifying striated toolmarks on bullets. The neural networks used in this study deal with binary signals derived from striation images. This signal plays a significant role in identification, because this signal is the key to the individually of the striations. The neural network searches a database for similar striations by means of these binary signals. The neural network used here is a multilayer network consisting of 96 neurons in the input layer, 15 neurons in the middle, and one neuron in the output layer. Two signals are inputted into the network and a score is estimated based on the similarity of these signals. For this purpose, the network is assigned to a previous learning. To initially test the validity of the procedure, the network identifies artificial patterns that are randomly produced on a personal computer. The results were acceptable and showed robustness for the deformation of patterns. Moreover, with ten unidentified bullets and ten database bullets, the network consistently was able to select the correct pair.  相似文献   

17.
Frontal sinuses of Japanese skulls were radiographically examined from the view point of identifying individuals. The system of classification of sinus was proposed, basing on the area size, the bilateral asymmetry, the superiority of side, the outline of upper borders, the partial septa and the supraorbital cells. Frontal sinus patterns could be divided into above 20,000 possible combinations by combining the class numbers in each classification item described above. The frontal sinus pattern of a given person was formulated as a code number which was determined by arranging the class numbers in each classification item as serial numbers. This identification system by the frontal sinus pattern should allow one to characterize each person. The application of this identification system to an actual criminal case was also described.  相似文献   

18.
Frequency of analytical characteristics is best estimated on glass recovered at random. However, as such data were not available to us, we decided to use control windows for this estimation. In order to use such a database, one has to establish that the recovered fragment comes from a window. Therefore, elemental analysis was used both for classification and discrimination of glass fragments. Several articles have been published on the subject, but most methods alter the glass sample. The use of non destructive energy dispersive X-ray microfluorescence (microXRF) for the analysis of small glass fragments has been evaluated in this context. The refractive index (RI) has also been measured in order to evaluate the complementarity of techniques. Classification of fragments has been achieved using Fisher's linear discriminant analysis (LDA) and neural networks (NN). Discrimination was based on Hotelling's T2 test. Only pairs that were not differentiated by RI followed by the Welch test were studied. The results show that neural network and linear discriminant analysis using qualitative and semi-quantitative data establishes a classification of glass specimens with a high degree of reliability. For discrimination, 119 windows collected from crime scene were compared: using RI it was possible to distinguish 6892 pairs. Out of 129 remaining pairs, 112 were distinguished by microXRF.  相似文献   

19.
Research on homicides followed by suicides has largely relied on very localized samples and relatively short time spans of data. As a result, little is known about the extent to which patterns within cases of homicide‐suicides are geographically specific. The current study seeks to help fill this gap by comparing twenty years of homicide‐suicide data for Sweden and a large U.S. county. Although some of the underlying patterns in the two countries are similar (e.g., decreasing rates), a number of important differences emerge, particularly with respect to incidence, weapons used, perpetrator age, and relationship of the perpetrator to the victim.  相似文献   

20.
构成要件的概念与构成要件的理论   总被引:1,自引:0,他引:1  
从客观和主观两个方面来说明犯罪成立条件的作法并非社会主义国家特有的方法.事实上,从罗马法开始直到19世纪中叶各国刑法理论都是如此.而将犯罪视为符合构成要件的违法有责行为的德日犯罪论体系则起源于19世纪中后期,其中居核心地位的构成要件理论经历了几次大的修正.促使德日构成要件理论发生重大转变的关键在于新康德主义哲学的影响.德日犯罪论体系在限制国家刑罚权方面具有优势.  相似文献   

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